Printing telegraph machine



April 29, 1941.

G. A. GRAHAM EI'AL PRINTING TELEGRAPH MACHINE Fil ed Sept. 23, 1936 6Sheets-Sheet 1 April 29, 1941. e. A. GRAHAM ETAL PRINTING TELEGRAPHMACHINE 6 Sheets-Sheet 2 Filed Sept. 23, 1936 wwWm 'April 29, 1941. e.A. GRAHAM ETAL 2,239,711

PRINTING TELEGRAYH MACHINE AvvEwrazS GEORGE-A @EAHAM HARRY .fiA/PMEQdrrazuay:

FIG-6,

April 29, 1941.

G. A. GRAHAM ETAL PRINTING TELEGRAPH MACHINE Filed Sept. 23, 1936 6Sheets-Sheet 4 //Vl/EN7"a/?J' 6501? GE ,4. GRAHAM H? v 14 APMER April29, 1941. GRAHAM ETAL 2,239,711

PRINTING TELEGRAPH MACHINE Filed Sept. 23, 1936 6 Sheets-Sheet 5 IrrOR/EKF April 1941- G. A. GRAHAM ETAL. 2,239,711

PRINTING TELEGRAPH MACHINE Filed Sept. 23, 1936 6 Sheets-Sheet 6 lA/70ES GEOEGAE 4. 6/24 #4 HAREVW 242/45? 5y M 1644; @QW Q m PatentedApr. 29, 1941 UNITED STATES PATENT OFFICE 2,239,711 I PRINTING TELEGRAPHMACHINE Application September 23, 1936, Serial No. 102,178

48 Claims.

(Granted under the act of March 3, 1883, as

amended April 30,

The invention described herein may be manufactured and used by or forthe Government for governmental purposes, without the payment to us ofany royalty thereon.

This invention relates to printing telegraph machines.

The invention is a further development and improvement based upon ourprevious application, Serial No. 725,968 filed May 16, 1934, Patent No.2,128,242, dated Aug. 30, 1938, which relates primarily to printingtelegraphy and printing-telegraph equipment constituting in effect aprintingtelegraph system wherein exact synchronization betweentransmitting and receiving processes is effected for each and everysignalling impulse by means of reed-operated escapements which time theprocesses with precision. In this invention we combine certain newelements with the devices previously described to provide a storagereceiver or permutation escapement selector and transfer devicesoperating upon translators as applied to particular forms ofprintingtelegraph equipment, including new features in keyboardtransmitters, printers and related structures as will hereinafterappear.

One of the main objects of this invention is to establish a permutedselection of elements in progression under the control of areed-operated escapement and to lock up that selection as a storagereceiver for sufficient time for subsequent printing processe Anothermain object is to employ this particular method of establishing aselection of elements to operate upon an electrical translator,including keyboard-transmitting, receiver-printing, andfunction-performing processes. Another main object is to employ thisparticular method of establishing a selection of elements to operateupon a mechanical translator, including keyboard-transmitting,receiver-printing, and function-performing processes.

Other important objects will become apparent to those skilled in theart.

The principles of the invention are illustrated in the accompanyingdrawings, in which:

Fig. 1 is a schematic drawing showing the basic principles of theinvention as applied to the electrical translator in a transmittingreceiving, printing-telegraph unit or station including a keyboardtransmitter and a particular form of printer;

Fig. 2 shows the selecting mechanism in detail with transfer elementcoordinated with the timing reed, start-stop magnet and transmittingdistributor as applied to set up a selection of electrical elements foroperation with the electrical translator.

Fig. 3 is an end View of the shuttle selector, selecting magnet, andtransfer clutch cam and lever;

Fig. 4 is a view within the shuttle selector stator, showing theselector magnet armature with respect to the marking and spacing tracksinternal to the stator frame;

Fig. 5 is an end view of the selector transfer;

Fig. 6 is a schematic diagram of the electrical components of theshuttle selector as applied to the electrical translator;

Fig. '7 is an end view of the electrical translator; The above figuresillustrate the principles of the invention involved in its applicationto an electrical translator and a continuously revolving type wheelprinter,

The following figures illustrate the principles involved in theirapplication to the mechanical translator and the stop at print typeWheel, in-

troducing a numberof new and novel interactive features and constitutinga greatly improved printing telegraph machine; I Fig. 8 is a schematicdrawing showing the basic principles of the invention as applied to themechanical translator in a transmitting-receiving printing-telegraphunit or station, including a new and novel keyboard transmitter, andapartic- 20 ular form of printer designed specifically for the -purpose;

Fig. 9 is an assembled front view of the shuttle selector coordinatedwith the reed escapement and distributors, the selector transferoperating 95 directly into a Baudot five-slotted disc translator, VI:and including the stop at print type wheel, paper roller, driving motor,transmission, and related structural details, In this view the keyboardtransmitter is removed, but certain cam elements 40 functioning inconjunction with the keyboard are shown at the extremity of thereed-escapement shaft;

Fig. 10 is an assembled view in side elevation of the shuttle selectorin relationship with the selector transfer connected to the Baudotfiveslotted disc translator, including the stop at print type wheel,paper roller and carriage, printing hammer mechanism, transmission,functional cam group, and keyboard transmitter with cam releasetransmitting contact combination including keyboard lock and restorefeatures. The details between the keyboard contact release cams and theshuttle selector; i. e., distributors, reed mechanism, etc., are removedin this figure; and Fig. 11 is a side View of the transfer cam lever,

being also representative of other cam levers operating on the gang camgroup.

We will first describe the various elements of the invention as appliedto the electrical translator and continuously operating type wheelprinter. Reference is made to Fig. 1, in which the intention is torepresent one complete transmitting-receiving printing-telegraph stationconnected to an identical distant station (not shown) by line and groundconnection. Obviously any complete circuit connection between the twostations, wire or radio, is within the scope of the invention. Theelements shown within the dotted inclosure A constitute a conventionalBaudot saw-toothed bar, five-unit code, keyboard transmitter withkeyboard locking magnet and lock, which being well-known in the artrequire no detailed description here. The elements shown within theinclosure 13 represent the particular form of printer in this phase ofthe application, and are hereinafter described in detail. The detailsshown within the inclosure C represent schematically the resultingaction through a Baudot electrical translator or combiner, the physicalconstruction of which is shown by Fig. '7, and the detailed electricalconnections and assignment as regards functions and characters are shownby Fig. 6. This particular arrangement is considered novel in that themarkingspacing combinations are in the ratio 2-2-4-816, which is a veryeconomical arrangement, bearing in mind that the usual ratio is24-8-16-32. However, it is believed the operation of such translators isgenerally understood and the description may be confined moreparticularly to the resulting action of the components shown within theinclosure C of Fig. 1.

The numeral 48 represents a high-speed line relay with armature 43 andlocal contact 46.

Having introduced the more or less conventional elements of Fig. 1, wewill now describe the special devices acting upon these elements toproduce very desirable results. Let it be assumed first that the gearsI96, I34, I64 and 200 are driven in common from an electrical motorwhich is operating continuously.

The details which are shown mounted upon or above base 48 are shown inmore detail in Fig. 2, and reference is now made to that figure. GearI66 is not connected directly to shaft 165, but the shaft simplyprovides bearing for the gear. The gear drives one side of a friction orslip clutch I8I, which in turn engages a driven side of the slip clutchI82 and I83. The detail I 82 represents proper slip-clutch facingmaterial. Member IB3 carrying detail I32 is keyed to shaft I55, thustransmitting drive, and spring I 84 provides the required degree offrictional clutch engagement. In brief, shaft I65 is driven by gear I66through slip clutch ISI, I82, I83, and will rotate accordingly whenpermitted to do so by the reed-operated escapement mechanism IIZ, I14,I15.

The reed-operated esoapement mechanism is described in detail in ourprevious application, Serial #725,968, Patent No. 2,128,242, and hencebut a brief description will be sufficient here. A reed In of givenperiodicity is clamped in position at mounting H9. At rest the reed isheld in dotted position I'I2a. When permitted to vibrate by release ofstart-stop magnet armature I61, the reed operates through link I16, anescapement yoke I15 formed to present two pawls I'IEa and H52), whichescape the progressive movement of escapement pins I'Ma and I142) shown,and I'Mc, I'Md, lite, and H4 not shown but located in staggeredrelationship equidistant about the periphery of escapement hub H4. Theescapement hub I is keyed to shaft I95. Accordingly the reed I12controls the progression of shaft I65, which rotates or tends to rotatethrough the friction drive of slip clutch IilI, I82, I83 in six stepsfor each complete revolution of the shaft. The function of theelectro-mechanical performance of the reed start-stop mechanism 62, I91,III is to release the reed, permitting the reed to vibrate threecomplete cycles (six half cycles; i. e., from I'IZa to IlZb beingone-half cycle and return from I'IZb to I'I'Za being the other halfcycle) after which the start-stop mechanism stops the reed in theinitial position I'IZa. The shaft IE5 is then at rest, with clutchslipping, except when permitted to rotate in definite steps by thereed-operated escapement.

Shaft I65 carries a transmitting distributor 49 and a start-stopfunctional distributor 51 as well as a cam-operated contact combinationM, 38, 39, which function in the keyboard-locking circuit. Properbearings are provided for shaft IE5 at I'I3 and I86.

The details to the right of bearing I86 on mounting 49, includingselecting magnet 65 and details, constitute the shuttle selector andtransfer element operating into the electrical storage receiver. Thesedevices operating in combination with our reed-controlled escapement andsubsequently described devices to constitute a completetransmitting-receiving printing-telegraph station, may be regarded asone of the major objects of our invention.

The shuttle selector comprises a two-track stator I89 mounted upon base40; a rotor I90 to which are attached five shuttles, ISM, I901), I900,was, and I9Ile, the shuttles operating on one leg in either of tracksI89a or I99b; and a selecting magnet 65, the armature 66 of whichdetermines the track taken by the individual shuttles during therotation of the rotor I99. Cam I8! is a transfer function describedlater. An end View of the shuttle selector is shown in Fig. 3 and a planView of a section of the stator I$9 and of the selecting magnet armature(i5 is shown in Fig. 4. Referring again to Fig. 2, each shuttle, IBM. toI9Ile inclusive, is provided with another leg at right angles to the legwhich operates in tracks IEEla and I 892), and which we will termhereinafter as the transfer leg, as differentiated from the selectingleg. Whether the selecting leg is in track I89a (marking), or I892)(spacing), determines the position of the transfer leg, as for exampleshuttle I99c is shown in the spacing position, while the dotted linesshow the marking position for this particular shuttle. The othershuttles act in an identical manner; i. e., the armature E6 of theselecting magnet assigns each shuttle-selecting leg to either themarking track I89a, or the spacing track I891), in one rotation of therotor I 90 from start to stop position,

I thus setting the shuttle transfer legs in marking or spacing positionsas the case may be.

The selector transfer comprises a frame I92 which carries fivemarking-spacing cams, I92a, I921), I920, I92d, and I92e, in positionswhich coincide with the stop positions of the five shuttle transferlegs; a transfer shaft I91, which carries the frame I92, and which isshifted from the receive-selection position to the transfer-selectionposition by shift yoke I93, in engagement with drive pin I95; and atransfer-shaft bearing I95, which provides a key section operating in akeyway on the shaft to prevent the shaft from turning. The selectortransfer is shown in the re-- is in stop position, the selector transferoperates to the position shown by properly timed cam action throughlever I88 on shift yoke arm I93. The cam itself is a function of anothershaft described later. It will be noted in the figure that movement tothe receive-selection position as shown, serves to present the arms ofthe cams I92a to I92e, inclusive, against the shuttle transfer legs I90ato I90e, inclusive, thus setting the cams in either marking or spacingposition. The cams are so constructed as to remain in the position lastset. Cam I920 is shown in the spacing position, the dotted radial linedenoting the marking position. Upon the receipt of a given permutedselection from the shuttle selector, the transfer then is returned bytension of spring I94, cam lever I 88 permitting, to normal positionwith frame I92 hub against bearing I95, and as a result themarking-spacing cams I92a to I926, inclusive, transfer their selectionto the electrical switches of the storage receiver or electricalselector. I

A cross-sectional view of the physical construction of the electricalreceiver is shown by Fig. 2,

and the electrical relationship is shown by Figs. 1

operates the lever in contact with spring 84 thus establishing a spacingconnection. Operation of contact lever 85 to contact 86 constitutes amarking connection. The block I98, upon which all contact levers andsprings are mounted, is of insulating material and,- of course, properinsulation is provided between all current carrying members.

Referring again to Fig. 1, the details shown within the area inclosed bythe dotted lines and designated D represent features which perform twoprimary functions; via, to move the transfer frame, previouslydescribed, from normal or transfer selection position to receiveselection position; and to establish electrical continuity through theselector receiver switches, the translator, and the printing magnet orfunction magnet as the case may be. Gear I34 is normally rotating underdrive, as previously stated, hence shaft I and the driving side of thepositive clutch I32 are also rotating. Thedriven side of this clutch I3Iis held out of engagement by the rounded extension of arm I31, the'lipon I 3| being cam contoured to provide this condition. However, upondepression of arm I31 by the shuttle cam I81 the action about pivot I36is to raise the extension of arm I31 out of restraint of clutch I3I,thus permitting clutch engagement for one revolution only, whereupon I3Iis returned to the position shown. Spring I33 provides the requiredclutch engage action. In this one revolution of clutch I3I shaft I30 isalso rotated operating cam I29 upon cam lever I88 which serves'tooperate With transfer cam 1 shaft MI and hence paper roller I38.

the shift yoke arm I93 and selector transfer details of Fig. 2. Alsoshaft I30 drives the distributor arm I21 of the distributor I26,establishing continuity between Wires I25 and H0 for the interval ofsegment I28 during the one revolution of the shaft. Necessarily thegearing, cams and distributor are properly timed witih respect to eachother and to other processes.

As stated'above, the elements shown in the area inclosed by the dottedlines and designated B, represent the particular form of page printeremployed in this phase of the application. The printer comprises acontinuously rotating type wheel I52 supported on carriage I53 anddriven from shaft I56 by means of bevel gear I64; a printing hammer I54and hammer pin I54a cam operated from an intermediate shaft which isengaged t0 the drive of shaft I56 at the proper time by magnet I50 andarmature I58 action on positive clutch I51; a carriage-spacing mechanismwhich is gear driven on rack I55 the required distance each time clutchI51 is operated by the printing magnet I50; a carriage-return mechanismoperating when rack I55 is disengaged from the step forward gearing bymagnet I49 and armature I6I, the return power being derived from springI59 coiled in housing I60; a letters and figures shift consisting ofmagnets I41 and I48 which serve to raise or lower the paper roller I38on shaft I 4| in bearings I39 and I42 in guides and I43; and a line-feedfunction consisting of magnet I46 acting through armature ratchet I44 onratchet wheel I45 which serves to step Such features as paper guides andribbon feed are not shown, being more orless conventional features, andin order not unduly to complicate the drawing.

Now it will be apparent that a definite timing of various shafts, cams,distributors, type wheel, and magnets is required throughout thistransmitting-receiving printing telegraph mechanism.- As examples inthis respect the following relationship was used in the preliminarymodel and hence is pertinent to this description. The motor which drivesgears I66, I34, I64, and 200 operates at 2100 R. P. M. Gear I64 andhence shaft I56 and type wheel I52 operate at 550 R. P. M. Gear 200 andthe brush arm 20I of the translator also operate at 550 R. P. M. Theprinting hammer drive cam shaft and carriage space shaft on thedriven-side of clutch I51 operate at 2200 R. P. M. when the clutchengages under magnet I50 action. Gear I34 and resulting action operateat 412.8 R. P.-M. Gear I66 operates at 431 R. P. M. but, and this is aninteresting and vital feature, does not drive shaft I65 at this speedthrough the friction clutch I8I, I82, I83 because the rotation of shaftI65 is determined by the frequency of the reed escapement I14, I15. Theclutch simply exerts turning moment to the shaft. The natural frequencyof vibration of the reed I12 is 19.5 cycles per second acting in 3-cycleescapement on shaft I65, hence shaft I65 performs one revolution inprogressive steps at the rate of 390 R. P. M.

With further reference to Fig, 1, let us now consider a typical exampleof operation through all processes from the striking of a key at onestation to the resulting printing of the designated character, or theperformance of a function at that same station and at the distantstation. It is assumed that the circuits and equipment at the distantstation are identical to that shown for the local station in Fig. 1. Thegears I 66,

I34, I34 and 230 at both stations are revolving under motor drive. Theline to the distant station is connected at L. A ground return isprovided at 2 and battery at 3. The line circuit in normal state is frombattery 3 by wire 4 to contact lever 22, contact 23, wire II, wire I3,relay winding 48, Wire to distant station and through an identicalcircuit with distant battery aiding to ground, return by 2 to battery 3.Transmitter bars 25, 23, 27, 28 and 28 and universal bar 24 are to theright as shown with contacts II, I3, I9, 23 and 2| open. The keyboardlockingmagnet is de-energized because the circuit, battery 3, magnet 33,wire 31, cam lever 33, cam contact 33, wire 33, return to battery 3, isopen at contact 39. Line relay 48 is energized because, as describedabove, the line circuit is closed and hence armature 43 is closed withrespect to contact 43 setting up a parallel circuit of two branches, oneof which holds energized startstop magnet 62 and the other holdsenergized the selector magnet 65. The respective circuits are, battery3, wire 4, wire 53, start-stop magnet 62, wire 6| to distributor 51,distributor arm 53, segment 60, wire 45, contact'46, armature 43, wire62, wire 35 return to battery 3; and battery 3, wire 4, wire 34,selector magnet 65, wire 41, contact 46, armature 43, wire 42, wire 36return to battery 3. The fact that the start-stop magnet is energizedand armature I6'I held down results in the reed II2 being held at restin position i'I2a under latch I'II, which in turn means that escapementpawl I'I5a is restraining hub I'I4 from movement at pin II4a and henceshaft I35 is at rest with clutch IBI, I82, I83 slipping although gearI66 is revolving. Distributors 49 and 51 and cam wheel 4| as well as theshuttle selector are at rest in normal state. The fact that the selectormagnet is energized at this timehas no particular significance otherthan circuit simplification.

The selector transfer I92, is in its normal position, which is that oftransfer selection (to the right in Fig. 2) with the last receivedselection of marking-spacing permutations set up in the switches 79 to9| inclusive (that selection not shown). This circumstance is of nomoment at this time.

The translator C is running; i. e., the brush arm MI is sweeping thesegments, but this also is incidental because theselector-translatorprinter circuit is open at distributor I23. Thedistributor I26 is at rest with brush arm I21 on an inactive insulatedsegment. Shaft I30 and cam wheel I29 are at rest due to clutch I3I, I32,being disengaged, although drive side I32 is revolving. The printer B isat rest.

Having described the normal or at rest condition, let us assume key 32is depressed by the operator. Transmitter bars 26, 28 and 29 are movedto the left or marking position thus closing contact levers I3, I and I6with contacts I8, 23 and 2| respectively; and bars 25 and Z'I remain tothe right as shown in spacing position leaving contact lever I2 and I4open with respect to contacts I1 and I9. This permutative arrangementcorresponds to the letter G in the Baudot code. The universal bar isalso at the same time moved to the left opening contact lever 22 withrespect to contact 23, thus opening the line circuit at that point.

The opening of the line circuit releases line relay 48 at the localstation and at the distant station. Armature 43 releases, thusdeenergizing' the start-stop magnet 32 and the selector magnet 55 atbothstations. Accordingly, reed H2 is released by armature I61 and, bymoving from position I'I2a to H219, permits shaft I 65 to rotate frompin position H411 to the position of engagement of pin I'I4b onescapement pawl I151). The subsequent escapement actions are describedfully in our application, Serial No. 725,968, Patent No. 2,128,242.However, having been released shaft I65 will be permitted to rotate insix successive equidistant steps to stop position with armature I31down, reed II2 stopped in position HM, and pin I'Ma engaged onescapement pawl I'I5a. In the first half cycle of reed action the shaftI65, having rotated one-sixth revolution, positions distributor arm 53on segment 5|; distributor arm 53 on segment 59; cam wheel 4| liftaction on cam lever 33 to contact 39; and presents the shuttle selectorleg I930. (Fig. 3) to the selector magnet armature 66 (Figs. 3 and 4).The distributor arm 53 has now connected line wire I6 to transmittercontact H, which being open with respect to lever I2, constitutes aspacing interval. The movement of distributor arm 58 to segment 53simply had the effect of removing the windings of start-stop magnet 62from connection to the line relay contact 46, segment 59 being entirelyinsulated and disconnected from all circuits. As will be seen later,when distributor arm 53 reaches segment 68a, the start-stop magnet willbe energized in anticipation of the return of reed I'I2 to position II2aunder latch III on the sixth half cycle, and in order to give the magnetampletime for operation. The closure of cam lever 33 and contact 33 hasenergized the keyboard locking magnet 33 and hence locked up thekeyboard by means of armature bar 35. The shuttle selector magnet 65 istie-energized at this particular time, due to the line circuit beingopen at contact I? (spacing position), and line relay 48 contact beingopen is in spacing position also, with the result that the shuttleselector leg Nita is directed into the spacing track I89!) of stator I33by the selector magnet armature 66. These same actions occur at thedistant station, with the exception that at that station the keyboardtransmitter has not been actuated and is in the normal condition shownin Fig. l, with distributor 43 and the keyboard-transmitting contacts I!to 2| inclusive shorted out of the line circuit by wire II, universalbar contact 23, and lever 22.

The reed escapement now permits shaft I65 to rotate to the next pinposition placing distributor arm on segment 52. This is a markingsegment at this time because the keyboard transmitter lever I3 isagainst contact I8 (our initial assumption for letter G, 2, 4, 5, Baudotcode), and hence current from battery 3 flows through the line circuitenergizing local and distant line relays 48 and moving their armatures43110 marking position with respect to contact 43, thus energizingselector magnet 65 which moves armature 66 to marking position. Theshuttle selecting leg I 9027 (Fig. 3) is now presented to armature 66(Fig. 4), which directs the selecting leg into marking track I89a.

The process is repeated for three more half cycles of the reedescapement, permitting shaft I65 to progress distributor 'arm 50 tosegments 53, 54, and in turn. Segment 53 at this time is a spacingsegment, and segments 53 and 55 are marking segments due to thearrangement of the contacts and levers of the keyboard transmitter. Theshuttle-selecting legs I830, IBM and I9|le are routed consecutively bythe selecting magnet into marking-spacing tracks of stator I89 as ingthe fifth half cycle of the reed escapement, 5

distributor arm 58 contacts segment 69a of distributor 91 causing magnet62 to draw down armature IE'I. The reed H2 at this instant is movingfrom position I'I2a to I'I2b. Hence latch III is now down, awaiting thereturn of the reed on the sixth and last half cycle, and upon the reedpassing in under the latch the reed will be restrained from furthermovement.

In the sixthand last half cycle of the reed to stop position, shaft I65rotates to the initial stoppin I'I Ia. Distributor arm 90 stops onsegment 56; distributor arm 58 stops on segment 60; cam wheel 4|releases cam lever 38 from contact 39; universal bar 24 is released bymagnet 33 to return to normal, closing contact 23 and lever 22;

cam I91 operates cam lever I31 and shaft I95 positions the shuttleselector in the initial position shown in Fig. 3. All members of shaftI65 have returned to normal, the keyboard transmitter is normal and aselection has been set up,;

in the shuttle selector.

We will now see how this selection is transferred to operate through theelectrical selector and translator upon the printer. When cam lever I3!was operated, clutch I3I was permitted topsoengage clutch I32, causingshaft I38 to rotate cam I29. Cam I29 depresses the cam lever I 88, whichin turn operates the transfer shift yoke lever I93, shown in Fig. 2, toadvance the transfer shaft I91 and frame I92 to the receive-selection;35

position with marking-spacing cam arms I92a to I92e, inclusive, thrustagainst the set selection of the shuttle transfer legs I9I3a to I98einclusive. This action causes each marking-spacing cam l92a, I921),I920, I92d, and I928 to take either aAO marking or a spacing position asdictated by the positions of the individual shuttle transfer legs I991;I992), I900, I990. and I9Ile. Hence cam I92a is set in spacing position,cam I92?) in marking position, cam I92c in spacing position, and cams4.5

Further I92d and I 92a in marking positions. movement of shaft I38returns the entire transfer assembly to transfer position, and transfersthis selection to the electrical switches I9, 82, 85, 88 and 9|. lator Cis operating continuously; i. e., the brush arm 2M continues to sweepover the segments shown in detail in Figs. 6 and 7. In other words thefunction of the translator is to seek out a continuity path matching theselection set up in the electrical selector. At the instant thiscontinuity of path is found, pertinent printer action occurs asdescribed below.

With further reference to Fig. 1, the switches of the electricalselector are shown in the position set by the shuttle-selector transfer.Also vthe translator C is shown diagrammatically in the position wherecontinuity is afforded which in our assumption is the letter G. Needlessto say the G position of the type wheel of the printer 5 I26, thusclosing the circuitfrom battery through selector, translator andprinting magnet for the proper duration of time. This circuit is asfollows: battery 3, wire I25, distributor arm I21, segment I28, wireIIU,.selector lever I9 (spacing),

contact 2'2, wire 98,.segments 93 (spacing), brush-"7.5

Now it will be recalled that the trans- 5 94, strap I I I, brush 91,segments 98 (marking), wire II, contact 83, selector lever 82 (marking),wire I98, selector lever (spacing), contact 84,

wire I2, segments 99 (spacing), brush I90, strap H2, brush I03, segmentsI84 (marking), wire "I5, contact 89, selector lever 88 (marking), wireI89, selector lever 9I (marking), contact 92, wire 'Il, segment I07(marking), brush I96, strap II3, brush H9, character segments .8, wireI24, windings of print magnet I59, return tobattery 3 bycommon wire I5I.The print magnet armature I58 connects positive clutch I51 to driveshaft I96. A proper cam related tothe driven side of the positive clutchI51 delivers the thrust to hammer I54 which strikes pin ISM. The pinthrusts the type character G against the paper carried on roller I38, itbeing understood that a proper typewriter ribbon is interposed betweenthe type and paper. From the foregoing it will be apparent how any othercharacter or printer function is selected and performed.

We have now shown how we maintain exact synchronization between theprocesses of transmission and. reception, and in addition how wepermutatively set up a selection and transfer that selectionsubsequently to an electrical translator acting on printing processes.

Having described sufficiently the first phase of I our invention; i. e.,the application to the electrical translator and the continuouslyrevolving type wheel printer, and having established in the readers mindthe required background, we-will describe hereinafter the application ofthe principles involved to the mechanical translator and thestop-at-print type wheel, constituting in effect a new, novel, andcomplete printing telegraph mechanism or station, as will be appreciatedby those initiated in the art.

Reference is now made to Figs. 8, 9, 10, and 11.

.Fig. 8 is'a schematic drawing showing the principles involved and thetheory of operation, while on the other hand Figs. 9, 10, and 11 areactual construction drawings, showing the various parts in detail andthe location and relationship thereof. The same reference numerals areused or not so stated. It is believed that too frequent mention of crossreferences may be confusing rather than helpful.

In Fig. 8 the intention is to represent one completetransmitting-receiving printing-telegraph .station or unit connected toan identical distant station or unit (not shown) by line and groundconnection. Any complete electrical circuit connection between the twostations, wire or radio,

The principle of operation of such only one stunt bar to fall outward in'a coinicidence of slots. This circumstance is arranged -to effect thestoppage of the type wheel unit I52 at any one of 32 radial positions,there'being 32 possibilities in the five-unit code. The type wheelhaving'tstopped in 'the"selected position, certain sprinting, carriagestep forward, ribbon feedfetc,

functions occur as will be des ribed in detail hereinafter. Our purposeis to show how we operate upon these elements to effect our desiredresuit in the following sequence; keyboard operation setting up apermuted arrangement of transmitting contacts and releasing the reedescapement mechanism; reed escapement progression of the selectionprocesses; transference of selection to the translator with subsequentfunctional performance.

The mechanical transmission features; 1. e., from driving motor tovarious shafts, clutches, etc., should be understood first. The drivingmotor is 223 which we will assume to be operating continuously. Themotor drive is connected to shaft I35 through gears 224 and I34. It willbe noted that a gang cam group is mounted on sleeve I35) on this shaftI35 and the sleeve I30 is normally held out of drive by disengagement ofpositive clutch member I3I. In order not to break the continuity ofthought, we will return to the description of this cam group later.Shaft I35 transmits continuous drive through gears 225, 226, 227, andI66 to the vertical shaft 2. Accordingly it will be seen that thevertical shaft 2 II is in continuous rotation in the direction indicatedby the arrow. Now the vertical shaft 2I I is equipped with two frictionor slip clutches, one providing driving torque for the rotor I90 of theshuttle selector, and the other providing driving torque for the typewheel I52. The rotor I90 of the shuttle selector is equipped, at theupper section, with a frame carrying externally the five shuttles (asimilar arrangement to that shown in Fig. 3) and internally the frictionclutch I8I, I82, I83, and I84, while the lower tubular section isequipped with a bevel gear in engagement with the bevel gear 228. (InFig. 9 details I83 are the driven clutch members attached to the rotorI36; IBI is the driving member attached to the shaft 2H; details I82 areproper slip clutch material and the spring providing frictionalengagement is I84.) The bevel gear 228 is keyed to the reed escapementshaft I65, which is equipped with the escapement hub I14 in properrelationship to the reed-driven escapement I15. These features are fullydescribed in the first phase of this invention as Well as in ourapplication Serial No. 725,968. The reed is shown at I12 and the reedstart-stop magnet at 62. The reed escapement shaft I65 is equipped withthe start-stop functional distributor and also the transmittingdistributor 49 as previously described. The cams 243 and 2%, carried onthe end of the reed escapement shaft IE5, perform keyboard functions tobe described later. The feature to be emphasized at this point is thatthe vertical shaft 2 is rotating continuously, and tending to rotate theshuttle selector rotor I89 and the reed escapement shaft I55, throughtorque at the friction clutch IBI, I82, I83 and I84; but that theprogression of the shuttle selector rotor I90, and the reed escapementshaft I65, is determined by the performance of the reed controlledescapement I75. In other words, shaft 2 provides the drive, but theprogression of shaft I65 and rotor I96 is a function of the reedperformance.

As stated above, shaft 2 is provided with another slip clutch for thetype wheel I52. The type wheel is so constructed as to present type barsexternally in radial disposition as shown, and is equipped internallywith the friction clutch affording slip engagement with the verticalshaft 2i I.

(In Fig. 9 the type wheel driven members are 2%, the shaft drive member206, proper clutch material 2m, and clutch tension spring 209.) It willbe apparent that the type wheel is rotated or stopped, dependent uponthe action of the translator stunt bars 2 upon the stop member 2 I2attached to the type wheel.

Returning to the gang cam group mounted on sleeve I39, as stated above,this combination is normally motionless because positive clutch memberI3I is held out of engagement by lever I31. However, when shaft Iperforms one revolution, lever I31, pivoted at I35, is disengaged by camI81 permitting clutch engagement of I3! with I32; hence the gang camgroup performs one revolution and is then disengaged by lever I37. Thesecams perform functional features as follows: 23! operates the ribbonfeed; I29 operates the shuttle selector transfer shift arm I3 throughcam lever I88; 230 operates the print hammer I54 (Fig. 10) through camlever 232 on the down stroke and the carriage step forward ratchet arm231, through member 23 1 on the up stroke; 225 performs the functions(not shown) of carriage return, line feed, and figures and lettersshift, through trigger action of pertinent translator stunt bars 2M uponconnecting links. These latter features are not shown because it is notdesired to unduly complicate the figures.

Let us return now to the description of this application of the shuttleselector, transfer, and the direct action of transference of selectionto the translator. The rotor of the shuttle selector is I90 equippedwith the five shuttles ISM to Mlle, inclusive, which have selecting legsoperating in stator track ISBa marking or I891) spacing, the theoryhaving been previously described in connection with Fig. 4; i. e., theselecting magnet armature 55 at a given instant upon rotation of therotor I93 asigns each of the five selecting legs I9ila to Ififieinclusive to either the marking track I891; or the spacing track I891)dependent upon whether armature 55 is in marking or spacing position.The shuttle selector stator IE9 is supported by frames 2I9 and 220 (Fig.9), which also serve to support the translator housing 2I3. The shuttlesIQta to I9Ile, inclusive, also have the transfer legs at right angles tothe selecting legs, the transfer legs being positioned to act upon thetransfer cams I92a. to I926, inclusive. (These members are called camsbecause they are so termed in the description of the first phase of thisinvention and an effort has been made to preserve the same nomenclatureand detail numbers throughout insofar as practicable.) The selectortransfer, however, in this phase of the invention performs twofunctions; i. e., to transfer the selection from the shuttle selector tothe five translator discs M5 by direct mechanical action, and to resetthe translator stunt bars 2M. The selector transfer frame is I92, withthe transfer cams I92a to I92e, inclusive, pivoted about the lowersection, the transfer shift yoke I53 engaging directly above, and at theupper section is provided with a reset disc so formed as to reset any ofthe stunt bars 2I4 upon downward movement of the selector transferframe. This feature will be appreciated upon an examination of therelationship shown in Fig. 9. Also, upon downward movement of theselector transfer, the cams receive the selection from the shuttletransfer legs and hence assume marking or. spacing positions. Let usexamine the action of these cams I92a to I92e upon the five translatorpush-pull bars 'CZIGato 2I6e, inclusive. In marking position the camsforce the push-pull bar's out, and in spacing pos'i tion draw these barsin. The pin engagement of the cams into slots in the bars in conjunctionwith the V section in the housing above each cam afford this action uponoperation of the transfer frame. This action will also be appreciatedupon an examination of Fig. 9. Now the push-pull bars 2I6a. to 2I6einclusive in marking or spacing positions, set the pertinent translatorslotted discs 2I5 in marking or spacing positions by means of theindividual shafts 2I'Ia to 2I'Ie arranged about the translator housing2I3.

The keyboard transmitter is shown schematically in the lower right handsection of Fig. 8 and in actual construction in the lower lefthandsection of Fig. 10. This keyboard transmitter is new and novel innumerous respects and provides certain advantages over types developedto date. These advantages will become apparent to those skilled in theart as the description is continued, and are briefly as follows: equalthrow for all keys; the elimination of thrust action of key bars uponsaw-toothed lateral members, the lateral members being pivoted at theirextremities resulting in a reduction of frictional effects; theprovision of means for the assembly of code combinations on any keyWithout the limitations of being restricted to a given permutedarrangement of fixed saw-teeth on a number of bars; and the inclusion ofa uniform load cam combination directly on the reed-controlled shaft,which releases and restores the keyboard contact lever combinations aswell as operates in conjunction with keyboard lock members. Referringagain to Fig. 8, one key is shown at 32. The code bars common to allkeys and'pivoted each at two extremities on the same axis are 25, 26,21, 28, and 29. It will be noted that the permuted arrangement for eachkey with respect to the common code bars is accomplished by thedisposition of identical extension fingers in marking or spacingpositions. Projection of the fingers to the right of the key is markingposition and to the left of the key is spacing position. The universalbar 24 is acted upon by all keys. Upon depression of a given key (thekey 32 in Figs. 8 and 10 is shown depressed) the extension code fingersof that key rock the code bars 25, 26, .27, 2B and 29 into marking orspacing positions. The code bars in turn operate upon contact pawls 261,268, 269, 210 and 2lI which are pivoted on a common center line betweenthe code bars and the code transmitting contact levers I2, I3, I4, I5and I6. In stop or restore position the transmitting contact levers areheldaway from contacts I1, I8, I9, 26 and 2| by the release bar 256which is pivoted at 251 and 258, but in this position the bar permitsclosure between an additional contact combination; i. e., contact lever22 and contact 23 which may be termed start-stop contact members. Thecontact levers are insulated from the release bar. In Fig. 8 the releasebar is shown in the release position, its normal position being asindicated to the right by the dotted line. Now it will be seen that withthe release bar in normal position and all transmitting contact leversheld away from their respective contacts, and the start-stop contactcombination closed, the contact pawls 267, 268, 269, 216 and 2' are freeto receive a marking or spacing setting from the code bars. Upon beingset in the desired; position by key operation, simultaneous operation ofthe universal bar latch 266 permits the release bar 256 to move awayfrom the contact levers in turn, permitting the contact levers to maketheir respective contacts under the residual spring tension set in thecontact levers, if the contact pawls do not interfere (markingposition), and at the same time removes the start-stop contact lever 22from contact 23. The contact pawls do interfere, if in spacing position,and prevent the pertinent contact levers from closing with the contacts.Attention is invited to the fact that the release bar locks the contactpawls in position by the interposition of teeth on the release bar withrespect to pins on the contact pawls (see Fig. 10) and hence locks upthe keyboard.

The universal bar latch 266 is so arranged, that upon the depression ofa key the latch is removed from behind the extension 259 of the releasebar, thus permitting the release bar to move to the left under theaction of its retractile spring. Also the trip pawl 262, attached to theuniversal bar 24 which lifted the latch 266 from engagement with theextension 259 is in turn disengaged from lift action on latch 26!) bybeing cammed out of engagement by roller 263. The latch is accordinglyfree to fall in place behind extension 259 upon the release barreturning to normal. The reason for this feature is to pre-' ventrepetitive operation upon holding down a key. As arranged, a key must bedepressed for each and every operation.

We have discussed the release features of the bar 256. Let usnowdescribe the restore features of this bar, through theagency of thecam combination on the reed escapement shaft, which results in removingthe lock from the keyboard,

opening all transmitting contacts, and restoring the start-stop contactlever 22 to'close with contact 23. Before doing so, however, let usfirst invite attention to the pin 254 in the slot of link 253 and to thefact that this pin does not pre vent bar 256 from releasing and movingfrom the right or restore position ,to the left or release position upondisengagement of the keyboard latch 266. This pin performs a restorefunction, but does not prevent the release function. To continue, twocam discs 243 and 244 are mounted on the reed escapement shaft I65.Roller 252 operates on cam disc 243 and roller 25I operates on cam disc244. The relative positions in which these items are shown is that ofstart which of course coincides with that of stop. The roller 252 on camdisc 243 in conjunction with arm 245 and link 253 actually delivers therestore stroke to the bar 256 through pin 254; but throughout onerevolution of shaft I65, cam disc 244 and roller 25I have been buildingup tension in spring 249 delivers the restore stroke to bar 256 througharm 245, link 253 and pin 254, which is followed immediately thereafterby fall off of ro1ler,25I on cam disc 244, resulting in a setting asshown in the figures but with the bar 256 in the restored position tothe right rather than in the released position to the left. The .bar256. is shown in.

the released position for descriptive reasons to be used later on theassumption that a key has just been depressed. Obviously arms 245 and250 are pivoted at 24'! and 248.

Several miscellaneous items appearing in the figures have not beenmentioned up to this point and these should be described beforepreceeding further. In Fig. 8, the numeral 48 designates ahigh-speed-line relay with armature 43 and contact 46. In Fig, 10, thenumeral 2E3 designates an arm which restores any given type bar whichhas completed printing; I54a is the hammer pin operating upon thepresented type bar; I54 is the printing hammer; MI is a paper tube forstoring rolls of paper, should such be desired, although often paperwill be used as in the regular typewriter; the carriage is pivoted at240 to permit of shifting to the letters or figures position with thestep forward rack at 238 and the carriage return spring housing I63; and22I is the rack which supports the operating lever arms coordinated withthe cam group mounted on sleeve I30, the bearing center of the leversbeing shown at 222 in Fig. 9. One of these levers is shown in detail inFig. 11. As mentioned previously, certain additional functional featuresare mentioned in this description which are not shown in the drawingsdue to the desire not unduly to complicate the drawings, but theinteraction of the devices shown upon these functional features will beappreciated by those skilled in the art. As examples in this respect, ithas been shown how the translator stunt bars 2I4 effect stoppage of thetype wheel in character printing positions, but four of these stunt barsstop the type wheel in blank positions, the movement of the stunt barsbeing used tooperate trigger link members presenting function performingmembers to the action of cam 229. The functions in question are linefeed, carriage return, figures shift and letters shift. Also the ribbonfeed is driven from cam 23I in such a manner that every revolution ofthe cam serves to ratchet the ribbon progressively through a pinion geartransmission, this drive being automatically reversible.

With further reference to Fig. 8, let us now consider a typical exampleof operation through all processes from the striking of a key at onestation to the resulting printing of the desig- The two stations areconnected together by line r wire continuation at L and earth return at2. Obviously any electrical connection between the two stations iswithin the scope of the invention, Let us first describe the normalstate of the various elements before a key is depressed. The motor 223is operating continuously at both stations, and hence shafts I and 2Hare in continuous rotation, but the gang cam group on sleeve I 30 is atrest held out of drive at clutch I3I. All keys are up, latch 260 isbehind extension 259, the release bar 256 is to the right in restoreposition with contact levers I2, I3, I4, I5, and I6 away from contactsI'I, I8, I9, 20, and 2|, and with contact lever 22 closed with respectto contact 23. The distributor arm 58 is as shown with the brushcontacting segment 60 of the distributor 51, and the distributor arm isalso as shown with the brush contacting segment 56 of the distributor49. The start-stop cam combination 243, 244, 25I and 252 is as shown.The reed I12 is in position I'I2a held by armature latch I'II of magnet62. Escapement pawl I'I5a is opposing movement of pin H40. and henceshaft I65 and the shuttle selector rotor I33 are at rest with frictionclutch I8! slipping. The shuttle selector transfer I92 is in theposition shown in the figure, with the marking-spacing cams I82a to 1326in the positions of the last received selection, the push-pull bars2I6a. to

2 I6e, inclusive, and the translator bars 2I5 being similarly disposed.The type wheel is stopped at the last selected stunt bar 2I4 withfriction clutch 2G5 slipping. All functions are in normal position.

The line circuit is, starting with battery 3, wire 4 to contact 23,contact lever 22, wire II, wire I0, line relay 48, wire I, and by linewire to the distant station, whereby a similar circuit connection ismade through battery aiding to ground and return to battery 3 at ground2. The selector circuit is, battery 3, wire 4, wire 64, magnet 65, wire47, line relay contact 46, armature 43, and wire 42 return to battery 3.The selecting magnet 65 being energized, armature 66 is in markingposition. The reed start-stop circuit is, battery 3, wire 4, wire 63,start-stop magnet 32, wire 6|, distributor arm 58, segment 60, wire 45,line relay contact 46, armature 43, and wire 42 return to battery 3. Thestart-stop magnet is energized holding reed H2 in position I'I2a byarmature latch III,

We will assume that key 32 represents the letter G and is coded 2, 4, 5,marking, and I, 3, spacing, in the Baudot five-unit code, and that thiskey is now depressed as shown in Fig. 8. The universal bar 24 isoperated and code bars 26, 28 and 29, and contact pawls 268, 210 and 2Hare set in marking positions, while code bars 25 and 21 and contactpawls 261 and 269 are set in spacing positions. The release bar isreleased by latch 238 and moves to the left. Trip 262 is cammed out fromunder latch 260 by roller 263. Contact lever 22 is lifted off contact23, contact lever I2 is not permitted to close with contact I'I becausepawl 26'! in spacing position is interposed, contact lever I3 is closedwith contact I8 pawl 268 being in marking position, contact lever I4 isnot permitted to close with contact I9 because pawl 26!! in spacingposition is interposed, and contact levers I5 and I6 are closed withcontacts 20 and 2I., respectively, pawls 210 and TH being in markingpositions. In brief, the line circuit has been opened at contact lever22 and the code for the letter G has been set up in the transmittingcontacts.

At the distant station no key having been depressed, that station beingfor the time the receiving station, the keyboard contact combinationremains in normal position and preserves the continuity of line circuitat contact lever 22 throughout the subsequent operations.

The line circuit having been opened at contact lever 22 at the localtransmitting station, the line relay 43 is de-energized at bothstations, and from now on the performance being the same at bothstations, except for keyboard contact restoration, the description willbe confined to the local station with the understanding that theperformance is duplicated at the distant station. The line relayarmature 43 falls away from contact 46, de-energizing the selectormagnet 65, which releases armature 66 to move to spacing position, andalso tie-energizes the reed startstop magnet 62 and hence releases thereed I12 which moves from position I12a to position I12b on the firsthalf cycle. The reed driven escapement pawl I15a also moves to the leftfrom under pin I14a, thereby permitting shaft I65 to rotate until pin I145 is stopped by pawl I15b. Distributor arm 58 of the transmittingdistributor 49 moves to segment and contact lever I2 being in spacingposition, the line relay 48 remains deenergized and armature 43 beingopen with respect to contact 46, the selecting magnet 65 also remainsde-energized with the selecting armature 66 in spacing position. In theprogression of shaft I65 from pin position I14a to H419, the shuttleselector rotor I99 has also progressed to a corresponding angularposition and in so doing has presented the selecting leg of shuttleI9ila to be routed into the spacing track I891) by the armature 66 thenin spacing position. The distributor arm 56 of distributor 51 haslikewise moved from segment 68 to segment 59 which is insulated from therest of the circuit, the purpose being to remove the reed start-stopmagnet from the circuit throughout segment 59 in order that this magnetwill be inactive during that period. The reed I12 now returns fromposition I12b to position H201. and releases pin |14b at escapement pawlI151); thus permitting shaft I65 to rotate to the next pin position; i.e., pin I14c which is stopped by escapement pawl I15a. Distributor arm5|] of the transmitting distributor 49 moves from segment 5| to segment52, and contact lever I3 being in marking position, the line relay 48 isenergized through the circuit, battery 3, wire 4, contact lever I3,contact I8,

wire 6, segment 52, distributor arm 59, wire III,

relay 48, wire I, and by line wire through distant circuit of wire I,line relay 43, wire III, wire II, contact 22, contact lever 23 closed,wire 4, battery 3 aiding and return to local battery 3 at ground 2. Theenergized line relay 48 attracts armature 43 to contact 46, and henceenergizes the selector magnet 65 which places the selector magnetarmature 66 in marking position, thereby directing the selecting leg ofshuttle I961) into marking track I89a, it being understood that theshuttle selector rotor I96 progresses with shaft I65. In fact theangular movements of progression of distributor rotors 56 and 58 and theshuttle selector rotor are identical.

The process as described above is repeated for three half cycles of thereed in which the distributor arm 58 is permitted to rotate consecu-.

tively from segment 52 to 53, 53 to 54, and 54 to 55, in phase withdistributor arm 58 and with the shuttle selector rotor I99, therebyassigning the selecting leg of shuttle I9|Ic to spacing track I891), ofshuttle IBM to marking track IBM, and of shuttle |9lle to marking trackI89a, as determined by the position of contact levers I4, I5 and I6 withrespect to contacts I9, 20, and 2| and the subsequent performance of theline relay 48 and the selecting magnet 65 in spacing and markingpositions. Upon the arrival of distributor arm 58 on segment 69a ofdistributor 51, it will be noted that the start-stop magnet 62 is thenconnected to battery, causing-operation of armature I61 in anticipationof the return of reed I12 under latch III. The sixth or last half cycleof the reed now occurs; '1. e., the reed moves from position II2b toinitial position I12a. and in so doing is locked in that position bylatch I1I. Shaft I65 rotates from escapement pin I14 to escapement pinI14a whichis the initial or stop position and is held there byescapement pawl I15a. In this progression of shaft I65, the cam group243 and 244 come into action, causing arm to pull upon arm 245 throughtension of spring 249, that tension having been built up throughout therevolution of cam 244 on roller 25I,and when roller 252drops into thestartstop depression of cam 243, this spring tension is exerted torestore bar 256 through link 253. The keyboard and transmitter are nowreturned to normal, with all transmitting contact levers open withrespect to the contacts, and with the start-stop contact lever 22 closedwith respect to contact 23; with latch 260 engaged behind extension 259;and with key 32 restored under action of spring 266. The line circuit isnow closed as at the start of our operational example. In theprogression of shaft I65 from the fifth to the sixth position, rotor 58of the distributor 46 moves from segment 55 to the initial insulatedsegment 56, and rotor 58 of distributor 51 moves from segment 6Iiatosegment 66, thereby restoring the connection 6| of the start-stop magnet62 to operation from the line relay 48 armature and contact combination43 and 46. Shaft I65 in this same progression presents cam I81 tooperate clutch arm I31 after which, as stated above, shaft I65 stops atescapement pin position I14a. Now the shuttle selector rotor I 96 beingthe driving member for shaft I65 has performed the same angularprogression and is also stopped by virtue of the gear connection withshaft I65. The position in which the shuttle selector rotor stopscoincides with its starting position, and all shuttles have been set inthe marking-spacing code for letter G, with their transfer legspresented for the subsequent action of the selector transfer I92.

When the cam I81 operated clutch arm I31, the positive driven clutchmember I3I was permitted to engage the driving clutch member I32 underaction of spring I33. As characteristic of the action of the particulartype of clutch and arm shown, one revolution of the clutch member |3|again disengages that member by means of the cam contoured surfaceacting on the rounded extremity of arm I31. However, in that revolutionclutch member I3I drives the sleeve I of the gang cam group mountedthereon. These cams are contoured to perform their various functions ina definite sequence.

Cam I29 is the first to operate upon cam lever I88, which in turnoperates the transfer shift yoke arm I93 about pivot I9I. The camthrusts roller and cam lever I88 up (normally held down and restored byspring I94, Figs. 10 and 11), hence thrusting arm I93 up and, beingpivoted at I'9I, the yoke engaging the transfer frame I 92 down; Thisaction presents the marking-spacing'cams I92a to I92e, inclusive, to theshuttle transfer legs |9Ila to I906, inclusive, which latter having beenset I 9%, I 9901, and I90e marking and,

I991; and I980 spacing, transfer that selection to the transfermarking-spacing cams as I92b, I92d, and I926 marking, and I92a and I92cspacing. As the transfer frame I92 moved down, the reset disc at thetop' of the frame restores the translator bar 2 I4 (previously selected)to the no-selection position, hence all bars are aligned receptive to aselection. Upon cam I29 now permitting cam lever I83 to move down underaction of spring I54, the transfer frame I92 is moved up; i. e.,returned to normal, and in so doing the marking-spacing cams I92'a toI92e, inclusive, operate upon the push-pull bars 2I6a to 2 I6e,inclusive,-setting those bars in the positions 2|6b, 216d, a'nd- 2I6'eImarking, and 2I6a, and 2I6C spacing, These push-pull bars in turn byrotation of shaft 2I'Ia to Hire, inclusive, set the five individualtranslator slotted discs 2I5 in the relationship 2, 4,, 5, marking and 1and 3 spacing. Properly timed thereto by the upward motion of the resetdisc of the transfer frame I92, one of the stunt bars 2E4 falls into thecoincidence of slots of the translator slotted discs, being drawntherein by an individual spring, and being in the assumption of ouroperational example, a stunt bar falling in the location designed tostop the type wheel I52 in the position with the letter G facing thepaper, and with that type bar extension under the hammer drive pin, andalso with that type bar in line with the printing slot. Obviously thetype wheel I52 has rotated under the friction drive of clutch 2% fromthe time of stunt bar reset to stunt bar select which in a properlytimed arrangement need never exceed one revolution of the type wheel.

Referring to Fig. 10, the type wheel character G is now properlypositioned with respect to the printing slot in the frame plate and alsoproperly positioned with respect to the hammer drive pin lE l-c. Thehammer I54 is now pulled down sharply by action of cam lever 232 andspring 233 upon properly timed fall off of cam 239, the hammer blowbeing transmitted through the hammer drive pin Ii'via to sharply rotatethe type bar of the letter G against the paper on roller I38, whereuponthe hammer is restored by cam action, the hammer pin by spring action,and the type bar by spring action on member ZIU. The return motion ofhammer I54 serves to carriage step forward through arm 234, acting onratchet 237 engaging rack 238.

Returning to Fig. 8, the gang cam group during its. rotation, andpreviously to the printing hammer actuation, operated cam 23! performingthe ribbon feed function, and presented cam 229 potentially active todeliver the power for such functions as carriage return, line feed,figure shift, or letter shift, had one of those functions been selectedinstead of, as in our assumption, the letter G.

As regards the rate of rotation of the vacuum shafts and otherrotational elements with respect to the vibrating reed, the followingrelationship has been found to be very satisfactory; reed 21 cycles persecond which escapes shaft I65, and the shuttle selector rotor I98 atthe rate of 420 R. P. M.; motor drive and hence rotation of shaft I35,450 R. 1?. hi; and vertical drive shaft 2I I, 600 R. P. M.

We have shown the advantages of our method of selection and transferselection under the progressive steps established by the reed drivenescapement. It is believed that the consistency of these processes willbe apparent to those skilled in the art. In addition, we have shown anentire interactive complete printing telegraph unit in Figs. 8, 9, and11 and the related description, which has many advantages other thanthose previously cited. The simplicity of design and compactness shouldimmediately become apparent. In fact, the model machine finallyconstructed was of the approximate dimensions, Weight, disposition ofthe usual conventional typewriter.

Changes and modifications are contemplated within the scope of theinvention as defined by the appended claims.

We claim;

1. In a printing telegraph system, a plurality of transmitting andreceiving machines, each machine being provided with means for thetransmission and reception of electrical impulses in combination atransmitting distributor assembly and a receiving shuttle selectorassembly; a transfer assembly responsive to said selector assembly; atype-bar-wheel assembly; a translator assembly operated by said selectorassembly to establish selective printing positions of saidtype-bar-wheel assembly; means including rotatable elements foroperating said transmitting distributor assembly and said receivingshuttle selector assembly in step by step unison, said means comprisingan escapemcnt mechanism, and a constant frequency device for positivelyactuating and controlling said mechanism.

2. In a printing telegraph machine, means including a circuit system forthe transmission and reception of signalling impulses; a selectingmechanism comprising a stator incorporating marking and spacing tracks,and a track switch; a rotor provided with shuttle members, said memberscarrying selector legs adapted to operate in said tracks; means forprogressing said rotor in definite and equidistant steps whereby saidselector legs are presented in consecutive order to the operation ofsaid switch, and Whereby said selector legs are routed into either amarking or spacing track, said means comprising an escapement mechanism;and a constant frequency device for timing and positively driving saidmechanism in exact phase with signalling impulses transmitted throughsaid circuit system.

3. In a printing telegraph machine, means including a circuit system forthe transmission and reception of code combinations of signallingconditions; a' selecting mechanism I comprising a stator and a rotor,said stator incorporating marking and spacing tracks, and a trackswitch, and said rotor including pivoted shuttle mem-- bers; selectinglegs actuated by said members and selectively operable in said tracks;means for actuating said switch whereby said selecting legs are directedinto either a marking 0r spacing track in exact phase relation with codecombinations transmitted through said circuit system, said meanscomprising an escapement mechanism; and a constant frequency device fortiming and positively driving said mechanism.

4. In a printing telegraph system, a plurality of stations and means ateach station for the transmission and reception of signalling impulses;a selecting mechanism at each station comprising a stator componentincorporating marking and spacing tracks, and a track switch; a rotorcomponent including pivoted shuttle members and selecting legs operativein said tracks and actuated by said members; a set of transfer elements;means responsive to electrical code signals and operative with saidtrack switch to direct said selecting legs into either a marking orspacing track, and for effecting the permutative radial disposition ofsaid transfer elements; an means for maintaining exact synchronismbetween electrical and mechanical processes of selection and transfercomprising an escapement mechanism; and matched reeds of constantperiodicity for timing and positively driving said mechanism at eachstation.

5. In a printing telegraph machine, means comprising a circuit systemfor the transmission and reception of code combinations: of signallingconditions; a shuttle selecting mechanism incorporating apair of tracks,andincluding shuttle members adapted to operate in said tracks;

and means in said circuit'system' for orienting said members intooperative position in said tracks, said means includingan'electro-magnetic device having its armature functioning as a switchand acting selectively in accordance with permutations of code signalstransmitted in said circuit system.

6. In a, printing telegraph machine, means comprising a circuit systemfor the transmission and reception of code combinations of signallingconditions; a shuttle mechanism incorporating a pair of tracks, andshuttle members adapted to operate in said tracks; an electro-magneticswitch for selectively actuating said members and for guiding the sameinto operative, position into said tracks; and means for maintaining theoperation of said switch in phase with said code signals, comprising anescapement mechanism;

and a vibrating reed of constant periodicity for timing and positivelyactuating said mechanism.

7. In a printing telegraph machine, comprising means for thetransmission and reception of signalling impulses; a selecting mechanismincluding a stator component incorporating marking and spacing tracks; arotor component carrying shuttle members, said members being providedwith selecting legs adapted to operate in said tracks; a track switchfor selectively actuating said legs; a drive shaft, and a driven shaftcarrying said rotor component; means comprising a friction clutch forcoupling the drive and driven shafts; and means for causing saidselecting legs to be presented in sequence for operation with saidswitch and .at a definite rate in predetermined incremental progression,said H means comprising an escapement mechanism operatively coordinatedwith the rotor component; and a constant frequency device for drivingand timing said escapement mechanism, and independently of therotational speed of the said drive shaft and clutch.

8. In a printing telegraph .machine, means comprising a circuit systemfor the transmission and reception of signalling conditions; a selectingmechanism comprising a stator component incorporating a marking trackand a spacing track; a track switch; a rotor component including shuttlemembers and cooperative selecting legs adapted to operate in saidtracks; a corresponding set of transfer legs; means responsive tosignalling conditions acting upon the progression of said rotor elementsto cause said switch to direct said selecting legs into either a markingor spacing track and for simultaneously effecting permutations in theradial disposition of said transfer legs; a transfer mechanism includingmarking-spacing cams; and means for operatively communicating thepermutations of said transfer legs to said cams in readiness to performsubsequent selective functions.

9. In a printing telegraph machine, means comprising a circuit systemfor the transmission and reception of electrical code signals; a shuttleselecting mechanism provided with a plurality of radial elementspositioned for permutable operation in accordance with said signals; atransfer mechanism comprising cam members operative withsaid elements;an electrical translator for effecting printing and other functionaloperations, said translator including a plurality of electrical switchesoperatively connected in said circuit system; and means operatively co-vordinating said transfer mechanism with said selecting mechanism wherebysaid switches respond to said permutable operation and in proper phaserelationship with said signals.

10. In a printing telegraph machine, means comprising a circuit systemfor the transmission and reception of electrical code signals; a shuttleselecting mechanism provided with a plurality of radial elements adaptedfor permutable operation in accordance with said signals; a transfermechanism including a plurality of pivoted cam members operativelypositioned relative to said elements to receive a permuted settingfromsaid selecting mechanism; means for operatively coordinating saidtransfer mechanism with said selecting mechanism; a translator providedwith slotted discs and including a plurality of pushpull bars foractuating said discs; and means for transferring said permuted settingthrough said bars to set said discs in marking or spacing position and.in accordance with said code signals.

11. In a printing telegraph machine, means comprising a circuit system.for the transmission and reception of electrical code signals; aselecting mechanism adapted for permutable operation in accordance withsaid signals, said mechanism being provided with a plurality of radialselecting elements; a transfer mechanism including a plurality ofpivoted cam members operative with said elements to receive a permutedsetting from said selecting mechanism; a mechanical translator havingstunt bars coordinated therewith, and a restore disc operating upon saidstunt bars; means for bringing the transfer mechanism into operativerelation with the selecting mechanism, and simultaneously to restoresaid stunt bars to normal position.

12. A mechanism in accordance with the preceding claim, in which themechanical translator includes a plurality of slotted code discs andpushpull bars adapted to'operate therewith; and means to cause said barsto rotate said discs into either marking or spacing positions inaccordance with the aforesaid permuted setting, and simultaneously toclear said stunt bars whereby any selected bar is placed in operativerelation with said slotted code discs.

- 13. In a printing telegraph machine, a selecting mechanism for thereception of permutable code combinations of electrical signalscomprising an electro-magnetic relay having an armature adapted tooperate in response to signalling conditions; a stator componentincorporating a marking track and a spacing track; a rotor componentincluding a plurality of pivoted shuttle members provided with selectinglegs adapted to operate in the tracks of said stator component; a switchactuated by said armature to cause said selecting legs to operate insaid tracks selectively in accordance with said signalling conditions;and means for progressing said rotor whereby said selecting legs areassigned to marking or spacing positions consecutively and in astep-wise manner.

14. In a printing telegraph machine, a mechanical translator comprisinga plurality of discs slotted'internally in permutable relationship inrespect to marking and spacing positions of said discs; a plurality ofstunt bars disposed transversely of said discs and operative with saidslots when in registry in accordance with a selection of one of saidbars and upon a given permuted arrangement'of said discs; a plurality ofpush-pull bars operatively coordinated with said stunt bars; a transfermechanism comprising means for moving said push-pull bars into markingor spacing positions and for disposing the same permutably with respectto said discs; means for restoring said stunt bars to normal position,and for acting upon said push-pull bars in their marking spacingmovement during one-half cycle of motion of a unit assembly, whichincludes a transfer selection frame and a translator stunt bar controldisc; and means for completing the action upon said push-pull bars intheir marking-spacing movement with respect to said discs, and forfreeing said stunt bars to permit a selection of said bars by said discsin the subsequent half cycle of movement of the same unit assembly.

15. In a printing telegraph machine, means for the transmission andreception of permutable code combinations of electricalsignals,including a selector assembly, and a translator assembly provided withselecting elements; a transfer mechanism operative to receive a permutedsetting from the selector and to transfer that setting to the selectingelements of said translator;

means for restoring said selecting elements of the translator to normalin one-half cycle of motion of a unit assembly, said assembly includinga transfer selection frame and translator stunt bar control disc; andmeans for completing the operation of the translator and for freeing theselecting elements of said translator to perform the function ofselection in the subsequent half cycle of motion of the same unitassembly.

16. A printing telegraph machine, comprising a selector mechanism, atransfer mechanism, a translator mechanism, and a type wheel mechanism;means operative through said mechanisms to effect the stoppage of saidtype wheel in a selected printing position; means for operativelycoordinating said mechanisms comprising a drive shaft having itslongitudinal axis common to all of said mechanisms, and includinginteracting mechanical elements disposed concentrically about the samecommon axis.

17. In a printing telegraph machine, a keyboard transmitter mechanism,omprising in combination a pluralityof keybars, acooperating leversystem including transmitting contact levers and contact elementsoperative to transmit permutative code combinations 'of electricalsignals; means responsive to an equal throw of said keybars to select apermuted arrangement of said contact levers; a universal bar mechanismoperative with the keybars; a release bar and means acting through saidmechanism on operation of any given keybar to unlatch said release barfor establishing a mechanical arrangement in marking spacingrelationship of said contact levers with respect to the said contactelements.

18. In a printing telegraph machine, a keyboard transmitter mechanismcomprising a plurality of keybars; a plurality of code bars operativewith the lceybars in marking-spacing positions; code fingers on saidkeybars adapted for permutable operation With said code bars; aplurality of contact levers and corresponding contact elements operativetherewith; and means for transferring the marking-spacing permutationsof said code bars to control the operative relationship of said contactlevers and contact elements, said means including a plurality of pawlsactuated by said code bars.

19. In a printing telegraph machine, a keyboard transmitter mechanismcomprising in combination a plurality of keybars each provided with codefingers; contact levers and contact elements operative therewith totransmit code combinations of electrical signals; and an intermediatelever system for operatively coordinating said keybars with said contactlevers, including transfer links and code bars, said bars being pivotedfor balanced rotational movement about a central fulcrum and havingoperative engagement with said fingers and said links at pivot points inbalanced relation to said fulcrum.

20. In a printing telegraph machine, a keyboard transmitter mechanism,comprising in combination a plurality of keys and keybars; a pluralityof pivoted code bars selectively positioned by said keybars, andintermediate pivoted pawls positioned in turn by said code bars;transmitting contact levers and contact elements operated through theinstrumentality of said pawls for the transmission of code combinationsof electrical signals; and means comprising a plurality ofinterchangeable fingers located in permuted arrangement on said keybarsand operatively engaging the said code bars to establish with eachkeying operation a corresponding permuted marking-spacing relationshipthrough said. code bars, intermediate pawls and contact levers.

21. In a printing telegraph machine, a keyboard transmitter mechanismcomprising a plurality of keys and keybars guided for equal verticalmotion; a plurality of balanced levers selectively positioned by saidkeybars, including a plurality of code bars carried by each keybar, andintermediate balanced levers acted upon by said last-named levers, andincluding transmitting contact levers, to effect a combination ofelectrical contacts in a signalling circuit; and means comprising aplurality of inter-changeable fingers located in permuted arrangement onsaid keybars and operatively engaging the said code bars to establishwith each keying operation a corresponding permuted marking-spacingrelationship through said code bars and contact levers to establish asequence of code signals.

22. In a printing telegraph machine, a keyboard transmitter mechanismcomprising a plurality of keys and, keybars; a cooperating lever system,including a plurality of balanced code bars pivotally mounted on eachkeybar; transmitting contact levers and corresponding contact elementsfor transmitting permutable code combinations of electrical signals;code extension fingers located in permuted relationship on each keybarfor operative engagement with said code bars; means comprisingintermediate con-'- tact pawls operative with said code bars to transferthe permuted operations of said bars to open and close said contactelements in accordance with the permuted relationship of said fingers;means for locking the contact levers in operative relation to saidcontact elements, said means comprising a release-restore bar providedwith projections and pins carried by the said transmitting contact pawlsadapted to assume locking engagement with the said projections; andmeans to release said locking'engagement in response to subsequentoperation of said bar.

23. In a printing telegraph machine, a keyboard transmitter mechanismcomprising means in combination with a keyboard for the transmission ofpermutable code combinations of signalling impulses, said meansincluding transmitting contacts and contact levers adapted to assumemarking-spacing positions in relation to said contacts; contact pawlsoperative with said contact levers; a release mechanism comprising arelease bar operative to release said contact levers to assumemarking-spacing positions with respect to said contacts, said releasebar including means operative with said contact pawls to 24. In aprinting telegraph machine, a keyboard transmitter mechanism comprisinga keyboard and means in combination therewith for the transmission ofpermutable code combinations of signalling impulses, said meansincluding transmitting contacts and contact levers adapted to assumemarking-spacingpositions in relation to said contacts; marking-spacingpawls operative with said contact levers; a contact lever releasemechanism comprising a release bar operative to release said contactlevers to assume marking-spacing positions with respect to saidcontacts, said bar being provided with means operative with said pawlsto lock up said keyboard; and means including a pair of cams coupled inopposition, a lever system operative therewith and spring means, one ofsaid cams functioning on one revolution to build up tension in saidspring means; and a link element for communicating energy from saidspring means at restore position of said cam to said release bar torestore the release mechanism to normal and to unlock said keyboard.

25. In a printing telegraph machine, a keyboard transmitter mechanismcomprising means in combination with a keyboard for the transmission ofcode combinations of signalling impulses, said means includingtransmitting contacts and contact levers adapted to assumemarking-spacing positions in relation to said contacts; an intermediatelever system including contact pawls operative with said contact levers;a release mechanism including a release bar functioning to release saidcontact levers to assume marking-spacing positions with respect to saidcontacts, said bar being provided with means operative with saidv pawlsto lock up said keyboard; means including start-stop cams and a leversystem operative therewith and with said release mechanism to restoresaid mechanism to normal; means for rotating said cams comprising adriven shaft and a prime mover differentially coupled thereto; anescapement mechanism for controlling the rotation of said driven shaftat a definite rate of progression, and independently of the speed of theprime mover; and a constant frequency device for timing and driving theescapement mechanism.

26. In a printing telegraph machine, a keyboard transmitter mechanismcomprising a keyboard and means coordinated therewith for thetransmission of code combinations of signalling impulses, said meansincluding transmitting contacts and contact levers adapted to assumemarking-spacing positions in relation to said contacts; intermediatepawls operative with the contact levers; "a release mechanismfunctioning to-cause I said contact levers to assume said marking-spamently of the speed of the prime mover; and a con-' stant frequencydevice for timing and driving the escapement mechanism.

27. In a printing telegraph machine, means for the transmission andreception of permuted code combinations of electrical signals, includinga selector assembly, a translator assembly having means includingselecting elements adapted to effect and control printing and machinefunctions; a transfer mechanism operative to receive a permuted settingfrom the selector and to transfer that setting to the selecting elementsof saidtranslator; means for restoring said selecting elements of thetranslator to normal and thereby timing said functions in one-half cycleof motion of a unit assembly, said assembly comprising the frame of saidtransfer mechanism and a disc member of formed periphery; and means forcompleting the operation of the translator and forfreeing the selectingelements of said translator to perform a new selection of functions inthe subsequent half cycle of motion of the same unit assembly.

28. In a printing telegraph machine, a selector mechanism, a transfermechanism, and a translator mechanism; means includin rotatable elementsfor operatively coordinating said mechanisms; a drive shaft fortransmitting movement to said elements, said shaft having itslongitudinal axis common to all of said mechanisms; and means forcontrolling the predetermined progression of said elements, said meanscomprising an escapement -which escapes the incremental progression ofthe selector independently of the rotational rate of said drive shaft;and a constant frequency device for timing and positively driving saidescapement.

29. In a printing telegraph machine, means comprising a circuit systemfor the transmission and reception of code combinations of signallingconditions; a transmitting selector distributor mechanism comprising arotary element; a receiving selector comprising a rotary element,

equipped with a plurality of radially disposed fin-v gers responsive toselecting means in said circuit system; driving means; a common drivenconnection between said rotary elements differentially coupled to saiddriving means; and means for effecting the rotation of the transmittingrotary element and the receiving rotary element simultaneously.

30. In a start-stop system of printing telegraphy, means comprising acircuit system for the transmission and reception of code combinationsof signalling conditions; a rotary element for selecting transmittingconditions; a second rotary element, equipped with a plurality ofextended and radially disposed fingers responsive to selecting means insaid circuit system connected to said first named element for selectingreceiving conditions; driving means for differentially operating saidconnected rotary elements; and means to effect the start-stop rotationof said elements simultaneously.

31. In a start-stop system of printing telegraphy, means comprising acircuit system for the transmission and reception of code combinationsof signalling conditions; a rotary element for selecting transmittingconditions; a second rotary element operating with said first namedelement for selecting receiving conditions; differentially coupleddriving means including a friction clutch interposed between said rotaryelements; means for effecting the rotation of said rotary elements in aplurality of steps from start to stop, the

number of steps being equal to the signalling code employed, andincluding an escapement mechanism; and means comprising a constantfrequency device for positively driving and controlling said escapementmechanism.

32. In a printing telegraph machine, means comprising a circuit systemfor the transmission and reception of code combinations of signallingimpulses; a transmitting selector distributor mechanism comprising aplurality of conducting segments and including a rotary elementselective with respect to a plurality of said segments allotted to thetransmission of each impulse; a receiving selector mechanism comprisingselecting members, including an electro-magnetically operated switch anda rotary element adapted to present said members to said switch whenactuated in response to received signals; a power drive, and means foroperatively coupling with said drive the rotary elements of saidtransmita ting selector and said receiving selector, said meansincluding a diiferential clutch to permit intermittent rotation betweensaid sets of elements and said drive; and means for controlling thesimultaneous rotation of said rotary elements of the transmittingselector and the receiving selector in predetermined progression, saidmeans comprising an escapement which escapes the incremental progressionof said rotary elements;

and a constant frequency device for timing and positively driving saidescapement.

33. In combination in a telegraph receiver; a set of permutation diskmembers; a corresponding set of reciprocating levers, and transferelements coupled thereto for positioning said members in differentcombinations; a corresponding set of selectors and electromagnetic meansoperative therewith for selectively controlling the setting of saidselectors in different combinations in accordance with received signals;a rotary member and controlling means for presenting said selectorssuccessively to said electromagnetic means; and means including a systemof cams and a camshaft carrying said cams for presenting said transferelements to said selectors.

at. In a printing telegraph system, a plurality of transmitting andreceiving stations, each station being provided with means for thetransmission and reception of electrical impulses; re-

ceiving devices at each station comprising a,

translator assembly including a plurality of segments and a rotary brushassembly, and a continuously rotating type wheel assembly; meanscomprising a magnet and drive pin operated by said translator to presentselected type into printing position; means including rotatable elementsfor operatively coordinating said assemblies; and means for maintainingstep by step unison between said elements, said means comprising anescapement mechanism, and a con stant frequency device which directlyand mechanically actuates and controls said mechanism.

35. In a printing telegraph machine, means for the transmission andreception of permuted code combinations of electrical signals, includinga sclect-or assembly; a type wheel assembly; a translator assemblyprovided with selecting elements adapted to effect the stoppage of saidtype wheel assembly at a selected position or to select machinefunctions; a transfer mechanism operative to receive a permuted settingfrom the selector and to transfer that setting to the selecting elementsof said translators; means for restoring said selecting elements of thetranslator to normal for releasing said type wheel into rotation,

or clearing said machine function selections in one-half cycle of motionof a unit assembly, said assembly comprising the frame of said transfermechanism and a disc member of formed periphery; and means forcompleting the operation of the translator and for releasing theselecting elements to effect the stoppage of said type wheel at a newselection or the selection of a machine function in the subsequent halfcycle of motion of the same unit assembly.

36. In a printing telegraph machine, means for the transmission andreception of code combinations of signalling conditions, including incombination, a type wheel assembly and driving means therefor, saidassembly being differentially coupled to and concentric with saiddriving means; a transmitting selector comprising a rotary element; areceiving selector comprising a rotary element; a driven connectioncommon to said rotary elements and differentially coupled to saiddriving means; and means to effect the rotation of the transmittingrotary element and the receiving rotary element simultaneously andindependently of the rotation or non-rotation of said type wheel.

37. In a system of the character described, means for the transmissionand reception of code combinations of signaling conditions, including incombination, a type wheel assembly and driving means therefor, saidassembly being differentially coupled to and concentric with saiddriving means; a rotary element selectively responsive to transmittingconditions; a rotary element connected to said first-named element andselectively responsive to receiving conditions; means for driving saidelements differentially; means for starting and stopping the rotation ofsaid elements simultaneously and as units; and means for subsequentlystarting and stopping the rotation of said type Wheel.

38. In a printing telegraph machine, means for the transmission andreception of code combinations of signaling conditions, including incombination, a type wheel assembly and means comprising a frictionclutch drive operative to rotate said wheel from one selected stopposition to another selected stop position; a rotary element selectivelyresponsive to received conditions, and a rotary element selectivelyresponsive to transmitting conditions, said elements being operativelycoordinated; differentially coupled driving means for said rotaryelements; means comprising an escapement mechanism for escapin therotation of said rotary elements in a plurality of steps from start tostop, the number of steps being equal to the signaling code employed;and means including a constant frequency device for positively drivingand controlling said escapement mechanism.

39. In a printing telegraph machine, means for the transmission andreception of code combinations of signaling conditions, including thecombination, a stop at print type wheel and means comprising adifferential drive for rotating said wheel from selected position toselected position, said type wheel being concentric with said drive; areceivim selector mechanism including selecting members; a rotaryelement, an electromagnetic switch operative with said element andresponsive to received signals; a transmitting selector mechanism havinga plurality of conducting segments allotted to the transmission of eachimpulse, and including a rotary element selective with respect to saidelements; a power drive, and means differentially coupled thereto forrotating the rotary elements of said receiving selector and

